Graham also said he was told by senior executives he was being overzealous in his efforts to make the plant safer.

Near the end of the hearing, Chambliss questioned Graham aggressively. He twice said he doubted Graham's sincerity and cut him off before he could answer a final question.

But U.S. Sen. Patty Murray, D-Wash., who chaired the panel - the subcommittee on employment and workplace safety - let Graham answer.

Chambliss is not a member of the subcommittee. He was invited as a courtesy because he is a Georgia senator, said subcommittee spokesman Matt McAlvanah.

Johnny Isakson, Georgia's other senator, is the top-ranked GOP member.

Hilder said he thinks Imperial suggested questions for Chambliss to ask Graham and accused the senator of a "cheap shot" against his client.

"He's more interested in discrediting Mr. Graham than discovering the facts, and I think he's the one who's being insincere," Hilder said.

Chambliss rejected Hilder's claims.

"I ask my own questions," the senator said. "That's what lawyers are paid to say."

He did say Imperial suggested questions to senators to ask Edwin Foulke Jr.

Foulke, head of the U.S. Occupational Safety and Health Administration, also testified Tuesday.

"I never saw them," Chambliss said of the questions.

Imperial spokesman Steve Behm said the company suggested questions to subcommittee members, but none to Chambliss for Graham.

Chambliss, who received a $1,000 campaign donation in June from Imperial's political action committee, did say he was "infuriated" at Graham.

"He said he was responsible for safety at the plant," Chambliss said. "He talked about ... how dangerous it was. ... But he did not insist to Imperial management that the plant be shut down until it was cleaned up."

But Graham testified Tuesday that he did do that.

"I told Mr. Sheptor I was surprised we hadn't killed anybody already because the plant was so dangerous," he said.

Chambliss acknowledged that Graham said that - but only after being prodded.

At the end of the hearing, Murray told Graham that "your future employment is of great interest" to her, Isakson and U.S. Sen. Edward Kennedy.

Kennedy, D-Mass., chairs the Health, Education, Labor and Pensions Committee, of which Murray's panel is a subcommittee.

McAlvanah said the senators will use their influence to make sure Imperial doesn't punish Graham for his testimony.